Prothesis (Word Sounds)

Bob Dylan 1961
One type of prothesis is a-verbing--that is, the addition of the prefix a- to the beginning of a verb form. An example of a-verbing appears in the title of the Bob Dylan song "A Hard's Rain's a-Gonna Fall" ( The Freewheelin' Bob Dylan, 1962). (Sigmund Goode/Getty Images)

Prothesis is a term used in phonetics and phonology to refer to the addition of a syllable or a sound (usually a vowel) to the beginning of a word (for example, especial). Adjective: prothetic. Also called intrusion or word-initial epenthesis

Linguist David Crystal notes that the phenomenon of prothesis is "common both in historical change . . . and in connected speech" (A Dictionary of Linguistics and Phonetics, 1997).  

The opposite of prothesis is aphesis (or aphaeresis or procope)--that is, the loss of a short unaccented vowel (or syllable) at the beginning of a word. 

The intrusion of an extra sound at the end of a word (for example, whilst) is called epithesis or paragoge. The intrusion of a sound between two consonants in the middle of a word (for example, fillum for film) is called anaptyxis or, more generally, epenthesis.

Examples and Observations

  • "And it's a hard, and it's a hard, it's a hard, it's a hard,
    And it's a hard rain's a-gonna fall."
    (Bob Dylan, "A Hard Rain's A-Gonna Fall." The Freewheelin' Bob Dylan, 1962)
  • "My characters will hence forth go afishing, and they will read Afield & Astream. Some of them, perhaps all of them, will be asexual."
    (E.B. White in a letter to a New Yorker editor who changed the word fresh to afresh in one of his essays)
  • "[A prothetic sound is a vowel etc.] that has developed historically at the beginning of a word. E.g. the e of establish is in origin a prothetic vowel in Old French establir, from Latin stabilire."
    (P.H. Matthews, Oxford Concise Dictionary of Linguistics, 2nd ed. Oxford University Press, 2007)
  • "Old fond eyes, beweep this cause again."
    (King Lear in The Tragedy of King Lear, by William Shakespeare)
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Your Citation
Nordquist, Richard. "Prothesis (Word Sounds)." ThoughtCo, Aug. 26, 2020, Nordquist, Richard. (2020, August 26). Prothesis (Word Sounds). Retrieved from Nordquist, Richard. "Prothesis (Word Sounds)." ThoughtCo. (accessed May 28, 2023).